FLORA OF THE DISTRICT OF COLUMBIA. 109 



15. Carex stipata Muhl. 



Marshes, swamps, and swales; common. May 15-June 15. Nearly throughout the 

 U. S. 



16. Carex laevivaginata (Kukenth.) Mackenzie. 



Marshes, swamps, and swales; common. May 15-June 15. Mass. to N. C. and 111. 

 Leaves narrower than in the preceding. 



17. Carex canescens L. 



Swamps and bogs; Coastal Plain. Late May-July. Throughout the northern U. S. 

 Reported to hybridize freely. Our form has widely separate spikes (C. canescens 

 disjuncta Fernald.) 



18. Carex bromoides Schkuhr. 



Swampy woods on Alexanders Island, the only station known here. Latter part 

 of May. Eastern U. S. 

 Occasionally dioecious. 



19. Carex rosaeoides E. C. Howe. 



Swampy woods; not common. May. Mass. to Ga. (C. seorsa E. C. Howe.) 



20. Carex cephalantha Bicknell. 



Wet woods and swamps, Middle of May to middle of June. Throughout the U. S. 

 (C. stellulata cephalantha Fernald; C. atlantica of Steele's list.") 

 20a. Carex angustior Mackenzie. 



In damp woods near Paint Branch Swamp, June 25, 1915 (Standley 11751). North- 

 ern U. S., south to D. C. (C. stellulata angustata Carey.) 



21. Carex incomperta Bicknell. 



Moist soil; the commonest species of the group in our region. May-June. Mass. to 

 Mich, and Fla. (C. stellulata of Ward's Flora.) 



22. Carex interior Bailey. 



Edge of pool, Maryland shore opposite Plummers Island; Mount Vernon; also along 

 the Patuxent. Last of May and first of June. Throughout the U. S. (C. scirpoides of 

 Gray '9 Manual.) 



23. Carex howei Mackenzie. 



Collected June, 1882, Ward, no locality cited other than District of Columbia. Maaa. 

 to D. C. (C. scirpoides capillacea Fernald; C. interior capillacea Bailey.) 



24. Carex scoparia Schkuhr. 



Usually in low ground. May-Aug. Nearly throughout the U. S. 



25. Carex tribuloides Wahl. 



Low moist ground; less common than the preceding. July-Sept. Throughout the 

 LT. S., east of Rocky Mts. (C. lagopodioides Schkuhr.) 



26. Carex proj ecta Mackenzie. 



Not common, but found throughout the region. July-Sept. Northeastern TJ. S. 

 (C. tribuloides reducta Bailey; C. tribuloides moniliformis Britton.) 



27. Carex cristatella Britton. 



Meadows; mostly confined to the Coastal Plain. July-Aug. Northeastern U. S. 

 (C. cristata Schwein.) 



28. Carex albolutescens Schwein. 



Wet soil of the Coastal Plain. May-July. Atlantic and Pacific coasts and Great 

 Lakes region. (C.foenea of Ward's Flora.) 



29. Carex straminea Willd. 



Wet soil. May-July. Eastern U. S. (C. straminea aperta of Ward's Flora.) 



30. Carex festucacea Schkuhr. 



Usually in wet soil. May-July. Northeastern U. S. (C. straminea tenera of 

 Ward's Flora.) 



31. Carex brevior (Dewey) Mackenzie. 



Low open ground. May- July. Eastern U. S. (C festucacea bre vior Fernald.) 



32. Carex alata Torr. 



Moist soil; Coastal Plain. May-July. Eastern L T . S. 



